Novembr 16-18—COLUMBIA, SOUTH CAROLINA: Annual show; The Columbia, SC Gem and Mineral Society; Fri. 10-6, Sat. 10-6, Sun. 12-5
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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Sun Sep 23, 2018 10:51 pm 
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Jason:

I was reading your post regarding the "glow" in certain stones, especially the blue ones, and your thinking that perhaps it was attributed in part to the copper. Of all the stones, rocks and gemstones that I possess, the most beautiful by far in color and in glow is a 42 carat phosphophyllite crystal from Bolivia. It is an amazing blue green color that actually looks better when not in the light. It glows like nothing else I've ever seen. It changes colors from blue to green depending on the light, but really shines in indirect light. It is truly a transcendent stone, but no copper in it. The second most beautiful is a pale Columbian emerald; included and chipped but very transparent and it also glows.

I am practicing faceting to try to be brave enough one day to work on the phosphophyllite. There is enough inclusion free material to get something around 20 carats if it wouldn't fall apart. I'm going to work on everything I can with horrible cleavage issues and softness before I try. The consensus seems to be to always keep the crystals intact as they're worth more, but who would ever buy one and pay what it's worth? The crystal is twinned but not perfect; it's had a few knocks, so I don't think a mineral person would be crazy about it. But wouldn't it be fantastic to have a 20 ct phosphophyllite in a pendant?

Regarding the paraiba tourmalines; I've seen some really crappy ones lately being called paraibas based on merely the copper. The best ones are beautiful, but so are many other things. My understanding is the copper bearing ones from Africa are being treated; heat and copper infusion; but I've seen a few that really looked good. I'm not up to date on detecting the infusion, but as they're a little too spendy for me there's been no point in educating myself. Aren't they treating some of the Paraibas, too?

Interesting discussion and fun read!


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Mon Sep 24, 2018 12:46 pm 
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Copper infusion?
Where did you get this information? I don't believe that to be accurate.

Debbie K, welcome!

Let'e start a new thread on the phosphophyllite. That is interesting on its own.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Mon Sep 24, 2018 6:53 pm 
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A friend of mine who is a GG was talking about it the other day, unless I hallucinated it, which I freely admit, is possible. It was after we were looking at some really pale greenish blue "Paraiba" tourmalines that some guy had on memo. I'll ask her where she heard about it; something about a similar process to the "andesine" labradorite.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Mon Sep 24, 2018 9:11 pm 
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In my opinion, the idea of copper being 'infused' into tourmaline is misinformation. No serious lab has ever confirmed it or seen any hint of it, and it is unlikely to be possible given tourmaline's behavior at higher temperatures.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Mon Sep 24, 2018 10:30 pm 
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Diffused tourmaline:
Overwhelming disproved.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Tue Sep 25, 2018 4:03 pm 
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I wish that some misinformaion could be removed from the internet. The great discovery of bulk diffusion of copper into tourmaline has been shone to be based on the misunderstanding of data generated by James. The GIA started a heating test on a large number of tourmaline samples and I don't think they ever bothered to complete the testing when the discovery was completely debunked. I see my fear, that even debunking the bad informaline would not clear the image of tourmaline,has come true. As I said in a post about the time the lie appeared. The assult on tourmaline's integrity is like humpty dumpty, it is imposible to put some peoples confidence, in the complex world of tourmaline, together again.

Bruce


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Wed Sep 26, 2018 11:07 am 
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Welcome Debbie K...glad you could stop by! Great post!

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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Wed Sep 26, 2018 1:19 pm 
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As Bruce can verify, heat treatment is rather routine, and I'm sure fracture filling has been attempted.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Wed Sep 26, 2018 5:38 pm 
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This is one of those times when you wish you hadn't said anything, and I don't pretend to know much of anything about treatments and I am only a baby gemology student. I've heard a little about Robert James and the andesine controversy years ago, but this wasn't in reference to that. I have no dog in that hunt, as they say here in Texas.

I asked my friend the GG to expound about the possible copper infusion of African tourmalines and what it was based upon. It was a discussion or paper of Dr. Hanneman's about the presence of copper in some of these tourmalines that other samples of rough from the same mines were lacking. I suppose conclusions were drawn, and perhaps they are erroneous. I know that he occasionally comments here, and perhaps there is a total misunderstanding which he could rectify. He and Alan Hodgkinson are my heroes; I've made most of the testing equipment that they came up with in "Affordable Gemology". I carried my books to my one and only trip to Tucson with me last year and the high point of my visit was getting them to sign their books and to actually meet them.

I heard this second-hand, and things definitely could have been lost in translation. Things like this make me grateful that I'm a carver and that almost everything I deal with is rough that most has had little or nothing done to "improve" it, except for perhaps heat and maybe irradiation. My interests are narrow and only extend to obtaining high quality rough, to accurately represent the stones that I include in my pieces and monkey curiosity about gemstones in general.

Sorry if I offended anybody.

Debbie K


Last edited by Debbie K on Wed Sep 26, 2018 5:49 pm, edited 1 time in total.

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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Wed Sep 26, 2018 5:44 pm 
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Perhaps your friend is confusing Dr. Hanneman with Ted Themelis.
Dr. Hanneman has never expounded on the diffusion of copper...in anything, to my awareness.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Wed Sep 26, 2018 5:51 pm 
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Barbra:

Next time I see her, I will try to find out.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Thu Nov 08, 2018 5:50 am 
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Barbra Voltaire wrote:
As Bruce can verify, heat treatment is rather routine, and I'm sure fracture filling has been attempted.


Hi Brabra,

I can confirm about the fracture filling: we've seen a couple of tourmalines in Bangkok with foreign substances in fissures.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Fri Nov 09, 2018 1:39 am 
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Dioptase wrote:
Barbra Voltaire wrote:
As Bruce can verify, heat treatment is rather routine, and I'm sure fracture filling has been attempted.


Hi Brabra,

I can confirm about the fracture filling: we've seen a couple of tourmalines in Bangkok with foreign substances in fissures.



Agree - bought this year 3 quite nice „Paraiba“ from Mozambique.
SI to LI clarity.

In a larger long pear I can see a typical flash effect in the microscope.

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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Fri Nov 09, 2018 4:41 am 
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Fracture-filling, yes. I’ve seen them. Copper infusion.....I highly doubt. I go to Bangkok often and trying to grab decent-priced, glowy, copper-bearing tourmalines when I see them.

The supply has been becoming less and less these couple of years. If there’s copper infusion, many goods would be all over the place. What’s in Bangkok market lately are “Paraiba-colored” tourmalines from Afghanistan and some claimed from Pakistan. These are nice blue greens, most are not glowy (still nice color though) but not sold as “Paraiba”, so prices are decent. Some are even part of mixed colored lots so nothing unusual. They don’t look copper infused with no price premium. Also, the most stones with report of copper-bearing from small local labs (Most likely they don’t have the more sophisticated equipment like Raman or ED-XRF) have obvious copper needles.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Fri Nov 09, 2018 6:28 am 
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The whole tourmaline "dyefusion" or "copper infusion" story is complete drivel.

Anyway... I've seen a Paraiba filled with epoxy resin but in our case, the worst offenders for the clarity enhancement were the rubellites. So buyers beware.


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